Gluten-Free Easy Almond Tart

In a food processor, combine gluten-free flour, salt and chilled butter. Pulse for about 10 seconds or until the mixture resembles fine crumbs. If you do not have a food processor, you can also do this by hand with a pastry blender or two butter knives.
Add the beaten egg and cold water. Run the processor until the mixture clumps mostly into a ball. If the mixture still looks very dry, add more water one teaspoon at a time.
Dump the mixture onto a sheet of plastic or parchment paper. (I like to cut up and wash plastic from things like thin plastic packaging to create reusable plastic sheets for rolling out dough.) Alternatively, you can roll out on a counter lightly sprinkled with gluten-free flour.
Gently knead the dough with your hands or through the plastic just until smooth, about 5 or 6 times, forming a flat disk.
Place another sheet of plastic or parchment over the disk. Roll out with a rolling pin until ¼-inch thick. Remove the top sheet of plastic or parchment. Transfer to a 9-inch tart or pie pan, peeling away the other layer of plastic after pushing the dough into the bottom and the sides of the pan.
Chill in the freezer for at least 30 minutes.
Preheat the oven to 350°F.

Prick the tart base with a fork. Place a circle of parchment larger than the pan on top of the tart and fill with pie weights or dried beans or rice.
Bake for 15 minutes. Remove the weights and parchment and return to the oven for another 5 minutes. Remove the tart shell from the oven and let cool.

Beat the room temperature butter and sugar together for 3 minutes, scraping down the bowl halfway through.
Add the eggs and extracts. Beat until smooth. Add the almond flour. Beat until smooth.

Spoon the filling into the tart shell. Smooth the top with an offset spatula.
Sprinkle the sliced almonds over the entire top.
Bake for 25-30 minutes or until the center only slightly wobbles when jiggled and the almonds are browned to your liking.
Cool completely before slicing.